wasp: st7789: Add a simple proof-of-concept display driver

1 files changed, 310 insertions, 0 deletions

diff --git a/wasp/drivers/st7789.py b/wasp/drivers/st7789.py
new file mode 100644
index 0000000..760af09
--- /dev/null
+++ b/wasp/drivers/st7789.py
@@ -0,0 +1,310 @@
+# Copyright (c) 2014 Adafruit Industries
+# Author: Tony DiCola
+# Extensive further hacking by Pimoroni and Daniel Thompson
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+import time
+
+__version__ = '0.0.2'
+
+BG_SPI_CS_BACK = 0
+BG_SPI_CS_FRONT = 1
+
+ST7789_NOP = 0x00
+ST7789_SWRESET = 0x01
+ST7789_RDDID = 0x04
+ST7789_RDDST = 0x09
+
+ST7789_SLPIN = 0x10
+ST7789_SLPOUT = 0x11
+ST7789_PTLON = 0x12
+ST7789_NORON = 0x13
+
+ST7789_INVOFF = 0x20
+ST7789_INVON = 0x21
+ST7789_DISPOFF = 0x28
+ST7789_DISPON = 0x29
+
+ST7789_CASET = 0x2A
+ST7789_RASET = 0x2B
+ST7789_RAMWR = 0x2C
+ST7789_RAMRD = 0x2E
+
+ST7789_PTLAR = 0x30
+ST7789_MADCTL = 0x36
+ST7789_COLMOD = 0x3A
+
+ST7789_FRMCTR1 = 0xB1
+ST7789_FRMCTR2 = 0xB2
+ST7789_FRMCTR3 = 0xB3
+ST7789_INVCTR = 0xB4
+# ILI9341_DFUNCTR = 0xB6
+ST7789_DISSET5 = 0xB6
+
+ST7789_GCTRL = 0xB7
+ST7789_GTADJ = 0xB8
+ST7789_VCOMS = 0xBB
+
+ST7789_LCMCTRL = 0xC0
+ST7789_IDSET = 0xC1
+ST7789_VDVVRHEN = 0xC2
+ST7789_VRHS = 0xC3
+ST7789_VDVS = 0xC4
+ST7789_VMCTR1 = 0xC5
+ST7789_FRCTRL2 = 0xC6
+ST7789_CABCCTRL = 0xC7
+
+ST7789_RDID1 = 0xDA
+ST7789_RDID2 = 0xDB
+ST7789_RDID3 = 0xDC
+ST7789_RDID4 = 0xDD
+
+ST7789_GMCTRP1 = 0xE0
+ST7789_GMCTRN1 = 0xE1
+
+ST7789_PWCTR6 = 0xFC
+
+class ST7789(object):
+    """Representation of an ST7789 TFT LCD."""
+
+    def __init__(self, spi, cs, dc, backlight=None, rst=None, width=240,
+                 height=240, rotation=90, invert=True, spi_speed_hz=4000000):
+        """Create an instance of the display using SPI communication.
+
+        Must provide the GPIO pin number for the D/C pin and the SPI driver.
+
+        Can optionally provide the GPIO pin number for the reset pin as the rst parameter.
+
+        :param spi: SPI instance to work with
+        :param cs: SPI chip-select Pin
+        :param backlight: Pin for controlling backlight
+        :param rst: reset Pin for ST7789
+        :param width: Width of display connected to ST7789
+        :param height: Height of display connected to ST7789
+        :param rotation: Rotation of display connected to ST7789
+        :param invert: Invert display
+        :param spi_speed_hz: SPI speed (in Hz)
+
+        """
+
+        self._spi = spi
+
+        self._cs = cs
+        self._dc = dc
+        self._rst = rst
+        self._width = width
+        self._height = height
+        self._rotation = rotation
+        self._invert = invert
+
+        self._offset_left = 0
+        self._offset_top = 0
+
+        # Initialize cs
+        self._cs.on()
+
+        # Setup backlight as output (if provided).
+        self._backlight = backlight
+        if backlight is not None:
+            backlight.off()
+            time.sleep(0.1)
+            backlight.on()
+
+        self.reset()
+        self._init()
+
+    def send(self, data, is_data=True, chunk_size=4096):
+        """Write a byte or array of bytes to the display. Is_data parameter
+        controls if byte should be interpreted as display data (True) or command
+        data (False).  Chunk_size is an optional size of bytes to write in a
+        single SPI transaction, with a default of 4096.
+        """
+        # Set DC low for command, high for data.
+        self._dc.value(is_data)
+        # Convert scalar argument to list so either can be passed as parameter.
+        try:
+            data[0]
+        except:
+            data = [data & 0xFF]
+        data = bytearray(data)
+        # Write data a chunk at a time.
+        for start in range(0, len(data), chunk_size):
+            end = min(start + chunk_size, len(data))
+            self._cs.off()
+            self._spi.write(data[start:end])
+            self._cs.on()
+
+    def set_backlight(self, value):
+        """Set the backlight on/off."""
+        if self._backlight is not None:
+            self._backlight.value(value)
+
+    @property
+    def width(self):
+        return self._width if self._rotation == 0 or self._rotation == 180 else self._height
+
+    @property
+    def height(self):
+        return self._height if self._rotation == 0 or self._rotation == 180 else self._width
+
+    def command(self, data):
+        """Write a byte or array of bytes to the display as command data."""
+        self.send(data, False)
+
+    def data(self, data):
+        """Write a byte or array of bytes to the display as display data."""
+        self.send(data, True)
+
+    def reset(self):
+        """Reset the display, if reset pin is connected."""
+        if self._rst is not None:
+            self._rst.on()
+            time.sleep(0.500)
+            self._rst.off()
+            time.sleep(0.500)
+            self._rst.on()
+            time.sleep(0.500)
+
+    def _init(self):
+        # Initialize the display.
+
+        self.command(ST7789_SWRESET)    # Software reset
+        time.sleep(0.150)               # delay 150 ms
+
+        self.command(ST7789_MADCTL)
+        self.data(0x70)
+
+        self.command(ST7789_FRMCTR2)    # Frame rate ctrl - idle mode
+        self.data(0x0C)
+        self.data(0x0C)
+        self.data(0x00)
+        self.data(0x33)
+        self.data(0x33)
+
+        self.command(ST7789_COLMOD)
+        self.data(0x05)
+
+        self.command(ST7789_GCTRL)
+        self.data(0x14)
+
+        self.command(ST7789_VCOMS)
+        self.data(0x37)
+
+        self.command(ST7789_LCMCTRL)    # Power control
+        self.data(0x2C)
+
+        self.command(ST7789_VDVVRHEN)   # Power control
+        self.data(0x01)
+
+        self.command(ST7789_VRHS)       # Power control
+        self.data(0x12)
+
+        self.command(ST7789_VDVS)       # Power control
+        self.data(0x20)
+
+        self.command(0xD0)
+        self.data(0xA4)
+        self.data(0xA1)
+
+        self.command(ST7789_FRCTRL2)
+        self.data(0x0F)
+
+        self.command(ST7789_GMCTRP1)    # Set Gamma
+        self.data(0xD0)
+        self.data(0x04)
+        self.data(0x0D)
+        self.data(0x11)
+        self.data(0x13)
+        self.data(0x2B)
+        self.data(0x3F)
+        self.data(0x54)
+        self.data(0x4C)
+        self.data(0x18)
+        self.data(0x0D)
+        self.data(0x0B)
+        self.data(0x1F)
+        self.data(0x23)
+
+        self.command(ST7789_GMCTRN1)    # Set Gamma
+        self.data(0xD0)
+        self.data(0x04)
+        self.data(0x0C)
+        self.data(0x11)
+        self.data(0x13)
+        self.data(0x2C)
+        self.data(0x3F)
+        self.data(0x44)
+        self.data(0x51)
+        self.data(0x2F)
+        self.data(0x1F)
+        self.data(0x1F)
+        self.data(0x20)
+        self.data(0x23)
+
+        if self._invert:
+            self.command(ST7789_INVON)   # Invert display
+        else:
+            self.command(ST7789_INVOFF)  # Don't invert display
+
+        self.command(ST7789_SLPOUT)
+
+        self.command(ST7789_DISPON)     # Display on
+        time.sleep(0.100)               # 100 ms
+
+    def set_window(self, x0=0, y0=0, x1=None, y1=None):
+        """Set the pixel address window for proceeding drawing commands. x0 and
+        x1 should define the minimum and maximum x pixel bounds.  y0 and y1
+        should define the minimum and maximum y pixel bound.  If no parameters
+        are specified the default will be to update the entire display from 0,0
+        to width-1,height-1.
+        """
+        if x1 is None:
+            x1 = self._width - 1
+
+        if y1 is None:
+            y1 = self._height - 1
+
+        y0 += self._offset_top
+        y1 += self._offset_top
+
+        x0 += self._offset_left
+        x1 += self._offset_left
+
+        self.command(ST7789_CASET)       # Column addr set
+        self.data(x0 >> 8)
+        self.data(x0 & 0xFF)             # XSTART
+        self.data(x1 >> 8)
+        self.data(x1 & 0xFF)             # XEND
+        self.command(ST7789_RASET)       # Row addr set
+        self.data(y0 >> 8)
+        self.data(y0 & 0xFF)             # YSTART
+        self.data(y1 >> 8)
+        self.data(y1 & 0xFF)             # YEND
+        self.command(ST7789_RAMWR)       # write to RAM
+
+    def white(self):
+        self.set_window()
+        for i in range(self._height):
+            self.data([255] * self._width * 2)
+
+    def black(self):
+        self.set_window()
+        for i in range(self._height):
+            self.data([0] * self._width * 2)